Sealing means for centrifugal pumps



Oct. 9, 1934. E. R. WILFLEY 1,976,532

SEALING MEANS FOR CENTRIFUGAL PUMPS Filed Jan. 9, 1934 Patented Oct. 9, 1934 PATENT OFFICE SEALING MEANS FOR CENTRIFUGAL PUMPS Elmer R. Wilfley, Denver, 0010., assignor to A. R.. Wilfley and Sons, Inc.,-Denver, 0010., a corporation of Colorado Application January 9, 1934, Serial No. 705,867

13 Claims. (Cl. 286-11) This invention relates to improvements in seals for centrifugal pumps. 7

Centrifugal pumps employed for handling water containing abrasives or corrosive liquids of any kind are preferably provided with an opening between the runner shaft and the wall of the opening through which the shaft enters the runner chamber, so as to prevent excessive wear at this point. Such pumps are also provided with a centrifugally operated sealing device that closes the opening about the shaft when the pump is rotated below a certain speed and when it is stationary and which opens the seal when the pump is operating. I I

In United States Patent No. 1,556,657 a pump of the type to which this invention refers has been shown and described and in the patented construction a sealing means has been provided for sealing the opening between the shaft and the runner housing when the pump remains stationary and for opening this seal during the operation of the pump so as to prevent the seal from becoming worn and ineffective. I

It is the object of this invention to produce a centrifugal sealing device of the type shown in the patent above identified which shall have means for protecting the fnovable parts against the action of abrasive materials and corrosive liquids which would otherwise make them inoperative.

In order to more clearly describe the invention reference will now be had to the accompanying drawing in which the same has been illustrated, and in which:

Fig. 1 is a section through a portion of a cen trifugal pump showing the means employed for opening and closing the seal between the shaft and the housing;

Fig. 2 is a top plan view of the cylindrical shell which surrounds the movable parts of the sealing device and the sealing member;

Fig. 3 is a section taken on line 3-3, Fig. 1; and

Fig. 4 is a section takenon line 4-4, Fig. 2.

In the drawing reference numeral 5 designates the runner shaft which is mounted for rotation in spaced ball bearings 6 located at opposite ends of the axle housing 7. The whole of the axle housing has not been shown because it forms no part of this invention.

Secured to the outwardly extending flange 8 of the axle housing is a short cylinder 9, whose open end is partly closed by a cylinder head 10. The cylinder head 10 has a hub-like portion 11 whose opening 12 is larger'than the outside diameter of the sleeve 13, which is secured to the shaft. The cylinderhead is provided with an inclined or frusto-conical' surface 14. The shaft 5 extends through the opening 12, and into the inby means of a nut 17. The construction of the runner is immaterial so far as this invention is concerned; but it is provided with a central hub portion 18 that extends towards the cylinder head 10 a'ndisseparated from the latter by a running clearance. The end of the hub 18, in the embodiment illustrated, is located in the intake opening 20.

Secured to the shaft is a sleeve 13 which ,is held against movement by means ofset screws 21, or other equivalent means. One end of this sleeve is provided with an outwardly extending flange 22, one side of which may beprovided with two cylindrical flanges 23 and 24, the latter of which extends intoa groove 25 in the cylinder head 26. The shaft is heldagainst longitudinal movement by suitable means as shown. Flange 22 has an. outwardly extending cylindrical wall 30 whose edge is provided with three pairs of spaced lugs 31, between which are located the arms 32 of the centrifugal weights'33; Pivot pins wall 3'7 and over ontothe retractor ring 36 in the manner shown in Fig. 1 and, when the shaft rotates, centrifugal force tends to move the weights 33 outwardly and to rotate the arms 32 about their pivots, thereby forcing the retractor ring 36 towards the flange 22 against the action of spring 35. When the shaft rotates slowly, or not at all, spring 35 holds the weights in the position shown in Fig. 1, in which position the retractor ring. 36 is moved towards the left in Fig. 1, as far as it can go;

Secured to the ring 38 which is integral with the retractor ring 36 and joined to it by the wall 37, is a cylindrical shell or housing 40. The main portion of this housing islarge enough to enclose the centrifugal weights 33 and to extend beyond the flange 23 as shown in Fig.1. One end of the cylindrical housing is provided with an inwardly extending flange 41 that overlaps the ring 38, in the manner shown in Fig. 4, and is secured to the latter by means of a screw 42. A flexible partition or diaphragm 43 has its outer edge clamped between the ring 38 and the flange 41 and is provided with a central opening of slightly smaller diameter than the outside of sleeve 13 and fits into a groove in the latter as shown most clearly in Fig. 4. A collar 44 is either attached to sleeve 13 or formed integral therewith and serves to hold the diaphragm in position. When the retractor ring is moved outwardly by the spring, or in the opposite direction by the centrifugal action of the weights, this movement merely flexes the diaphragm which forms a watertight partitio'n between-the sleeve 13 and the cylindrical housing 40. Pronular surfaces 47 and 'cross section, as shownin Fig. 4, and is that isadapted to engage the .13 has an outside diameter position it will be forced jectin'g from the flange, 41 of the cylindrical housingare anumber'of arms 45 that connect it with a ring 46. This ring has two spaced an- 48. Ring 49 hasa Z-shaped secured to the ring 46 by means of-screws 50. 'Ring A9 has a rabbet 51 in which is located-the of asealing member 52. This member is prefer- Jably held in place by means of screws 53. Member 52 is, preferablyformedfrom rubberized'fabric, which has been vulcanized and is provided atits outer end with a frusto-conical surface 54 surface 14 on the cylinder head .10. Whentheshaft is. stationary or rotating at a slow speed, spring 35 forces the surface 54 of the sealing member against the surface 14 and forms aseal between, the :inside of the pump and the space about the cylindrical sleeve 40. It will be seen from Fig. i4thatsleeve substantially the same as the inside 'diameterof, the sealing ring atthe point where the latter is'located so that moved into operative a'gainstthe outer sur-' face of the sleeve and also against theinclined when the sealing ring is surface 14, thereby forming a watertight seal. at this point when the shaft is rotating at a suf-.

flcient speed to make the pump operative, the

weights 33fwill turn abouttheirpivotpins 34 and o thatoccasionally some liquidsfrom 'Dfimpjwillf flow out not enter the ehamsr h xible diaphragm provid 'a watertigh wall betweenthe-outside of' the latte eittendsbeyondthe flange 22' and there-- fore before any 1 liquid has found its way to the openend pf 'the housing,'it will be thrown off by centrifugal force and the movable parts will therefore "be [protected against 5 the deleterious eifectofthe abrasives or corrosives contained in the liquid.

When the sealing ring 52 i worn to'such an connecting the said housing located to seal the devices for operating the first named sealing device from the opening around extent that it must be replaced this can be done the screws 50 accessible. By removing the screws 50, ring 49 can be removed, after'which the seal ing member can be removed from the ring: and replaced by a new one; This construction greatinner eiid I u between the shaft'gandl thecyiinder -head,'; but with the construction ide scribed, this liquid can b in which th spring 35 and the'weights33are- 13 and thejcylindrical housing and the means for normally holding when the pump is inactive and means for opening I ly simplifies the operation of replacing worn sealing members. In the construction shown in the patent above identified, a spring corresponding to spring 35 and weights corresponding to weights 33 and a sealing member corresponding to member 52 are employed, but no means is provided for protecting the movable parts against the effect of leakage at this point with the result'that abrasives and corrosives often come into contact with the spring and the weights and makes them inoperthe same whether used with a pump like that shown in the patent or like that shown'iin'this application and the claims should be construed withthis in view. Pumps of this type areoften used for raising liquids containing acids and other corrosive substances that would injuriously aifect the seal operating means and the present protective housing is equally eifective with :such

liquids.

as new is: o 1. Ina centrifugal pumphaving an opening around the shaft communicating with therunner chamber, a seal for controlling said opening,'and meansfor actuatingthe seal, the combination of a housing mounted on the shaft and enclosing the seal actuating means, the said housing having a flexible partition connecting it with the shaft and positioned between the seal actuating means and the opening and serving to protect said actuating means at all times from material passing through the opening around the shaft". 2. In :a centrifugal pump having an opening around the shaft communicating with the runner Having described the invention what is claimed chamber, a seal for'controlling said opening, and

and a flexible diaphragm connecting the-housing with the'shaft and forming with the housing a around the shaft and seal between the opening .the s'ealactuating'means',the said diaphragm be-r ing locatedbetween the said openiii'g and said Ina centrifugalpump having an opening around the shaftcommunicating with the runner chamber, a device for sealing said opening, means for normally holding said sealing device .;inv the closed position, the-sealing device to open positionwhen ,the pump is inoperation, the combination of a. housand means. for -moving ing connected to be operated by the seal actuating means and simultaneously therewith, said hous ing enclosing the means for holding the sealing device in the closed position and the means for opening the said device, and a flexible diaphragm with the shaft and the shaft.

4., In a centrifugal pump having an opening around the shaft communicating with the runner chamber, a seal for controlling said' opening, the said seal closed 1,976,588 said'seal when the pump is in operation, the combination of a housing connectedto be operated by said seal actuating means and simultaneously with the operation of the seal, said housing enclosing said operating mechanism and having a flexible partition between the actuating means and the opening and serving to seal the actuating means from the opening around the shaft.

5. A centrifugal pump having an opening around the shaft communicating with the runner chamber, a device movable with respect tothe shaft for sealing said opening, means for actuating the sealing device to close the said opening, means for moving the sealing device to the open position, a housing surrounding the shaft and enclosing the means for moving the sealing device in both directions, and actuated by said means,

and a flexible diaphragm connecting the housing with the shaft and forming with the housing a seal between the said opening around the shaft and the devices for actuating the first named seal to prevent injury to said devices from the material handled by the pump.

6. In a centrifugal pump having an opening around the shaft communicating with the runner chamber, a device for sealing said opening, means for normally holding said sealing device in the closed position, and means for moving the sealing device to open position when the pump is in operation, the combinationof a housing surrounding the shaft and connected tobe operated coincidently with said sealing device, the

said housing enclosing the means for holding.

the sealing device in the closed position and the means for opening the said device, and a flexible diaphragm connecting the said housing with the shaft and located to seal the means for operating the first named sealing device from the opening around theshaft.

'7. In a centrifugal pump having an opening around the shaft communicating with the runner chamber, a devicemovable with respect to the shaft for sealing said opening,resilient means for normally holding said device in the closed position, and means operated by centrifugal. force for-opening said sealing means when the pump is in operation, the combination of a housing surroundingthe shaft and connected to be operated coincidently with said sealing device, and by the same actuating means, thesaid housing'enclo'sing both sets of means for actuating the said sealing device, and a flexible diaphragm con-- necting the housing with the shaft and forming a seal between said opening around the shaft and the means for actuating the first named seal in both directions. v

8. In a centrifugal pump'having an opening around the shaft communicating with the impeller chamber, a sealing device for said-opening, means for moving said device to the closed position when the shaft is stationary, and means for moving said sealing device to open position when the shaft is rotating, the combination of-a housing upon which said sealing device is mounted, said housing enclosing the moving means, a flexible partition connecting one end of the housing with the shaft and forming with the housing a protective wall between the opening around the shaft and the seal actuating devices.

9. In a centrifugal pump of the type having a housing provided with a wall having an opening, an impeller shaft extending through the opening and terminating in the housing, the opening in the wall being larger than the outside diameter of the shaft, resilient means for 1 reached a predetermined value, means for prosealing theopening when the shaft is stationary and means for opening the seal after the speed of the shaft has reached a predetermined value,

means for protecting theresilient'means and the seal opening means from leakage through the- 80 opening in the housingwall, said means comprisingacylindrical housing enclosing the resilient closing means and the-seal-topening means and having one end connected with the shaft by means of a partition which is positioned between the opening and the two means.

10. In a centrifugal pump of the type having a housing provided with a wall having an opening, an impeller shaft extending through the opening and terminating in the housing the opening in the wall being larger than the outside diameter of the shaft, resilient means for sealing the opening when the shaft is stationary and means comprising a centrifugal device for opening the seal after the speed of the shaft has tecting the closing means and the seal opening means from leakage through the opening in'the wall, said means comprising a cylindrical housing enclosing the two means and having one end connected with the shaft by means of a flexible partition which is positioned between the open-- ing andthe two means. v I

11. In a machine of the class described and in which a shaft extends through an opening in a wall. the opening being somewhat larger than the shaft so as to leave an annular space about the. latter, means for sealing the opening when the shaft is stationary and for opening it when the shaft is rotated above a certain speed, said means comprising a cylindrical housing of .larger inside diameter than the outside of the is rotated above a predetermined speed, the

spring andthe centrifugal device being located in the.cha.mber formed by the cylindrical housing and the diaphragm.

a 12. In a centrifugal 'pump of the type having a runner chamber with an. intake chamber in communication therewith, one wall of the intake chamber having an opening, a runner shaft 1 extending through the opening and terminating within the runner chamber, the opening being larger than the shaft and having its wall provided with a sealing surface, and a ring slidably mounted on the shaft, means for controlling the action ofthe sealing ring comprising, a spring surrounding the shaft, one end of the spring engaging the ring. an abutment on the shaft for cooperating with the other end of the spring,

a centrifugal device carried by the shaft for mov- 14 ing the ring against the force exerted by the spring when the shaft is rotated above a predetermined speed, a cylindrical housing enclosing the spring and the centrifugal device, one end of the housing being connected with the ring, a diaphragm having an opening throughwhich the shaft extends, the outer edge of the diaphragm being connected with the housing so as to form a chamber for the spring and the centrifugal device, a ring carried by the cylindrical 1.50 4

housing between the diaphragm and the sealing surface said sealing ring carried by the last' named ring and so positioned that it will engage the'seaiing surface on the wallhaving the opening whereby, when the shaft rotates below a predetermined speed, the spring will move the sealing ring into operative position and when it rotates above that speed, the centrifugal device will move the'sealing ring into inoperativeposition, the cylindrical sleeve and thediaphragm serving to protect the spring and thecentrifugal device from the leakage.

13. In a centrifugal pump having a runner chamber, one wall or which has an opening for a runner shaft, the opening being larger than the shaft, a sealing ring slidable in the direction of the length of the shaft, resilientmeans for 'normally urging the sealing ring into operative position, centrifugal means carried by the shaft for moving the sealing ring into inoperative position when the shaft rotates above a certain speed, a cylindrical housing enclosing the resilient means and the centrifugal means, the end of the housing nearer the sealing ring being connected with the shaft by a partition, and means for transmitting motion from the resilient and the centrifugal means to the sealing ring.

, ELMER R. WILFLEY. 

